Fuel injector having a plurality of flow-through regions

Abstract

The fuel injector provides an oncoming flow out of spray-discharge orifices in a manner that reduces variance in the spray and flow-through characteristics variables. The fuel injector includes at least one excitable actuator and a valve element that is movable along a longitudinal valve axis, which collaborates in a sealing manner with a valve seat. Upstream of the valve seat, circumferentially a plurality of flow-through regions are provided, between which there are guidance regions for the valve element. The spray-discharge orifices downstream from the valve seats, whose number differs from the number of the flow-through regions, discharge the fuel finely atomized. At least two flow-through regions differ in size, such as circumferential width and/or radial depth, and/or contour. The fuel injector directly injects fuel into a combustion chamber of an engine using compression of a fuel/air mixture and spark ignition.

What is claimed is: 
     
       1. A fuel injector for a fuel injection system of an internal combustion engine, for direct injection of fuel into a combustion chamber, comprising:
 at least one excitable actuator and a valve element movable along a longitudinal valve axis an connectible in a sealing manner with a valve seat; 
 a nozzle body at a spray-discharge end of the fuel injector; 
 a plurality of flow-through regions are configured in the nozzle body and positioned circumferentially and upstream of the valve seat, between which, in each case, there are guidance regions for the valve element; and 
 a plurality of spray-discharge orifices downstream from the valve seat; 
 wherein a number of the plurality of the spray-discharge orifices is different from a number of the flow-through regions; and 
 wherein at least two flow-through regions differ from each other in radial depth, such that a flow of the fuel is uniform. 
 
     
     
       2. The fuel injector of  claim 1 , wherein the number of spray-discharge orifices is greater than the number of flow-through regions. 
     
     
       3. The fuel injector of  claim 2 , wherein five flow-through regions and more than five spray-discharge orifices are provided. 
     
     
       4. The fuel injector of  claim 1 , wherein the spray-discharge orifices are configured in a floor section of the nozzle body or in a separate spray-orifice disk, which is fastenable to the nozzle body. 
     
     
       5. The fuel injector of  claim 1 , wherein the spray-discharge orifices are aligned so that they run radially outwards inclined in a slantwise manner. 
     
     
       6. The fuel injector of  claim 1 , wherein the flow-through regions form longitudinal groove-like flow-through pockets. 
     
     
       7. A fuel injector for a fuel injection system of an internal combustion engine, for direct injection of fuel into a combustion chamber, comprising:
 at least one excitable actuator and a valve element movable along a longitudinal valve axis an connectible in a sealing manner with a valve seat; 
 a nozzle body at a spray-discharge end of the fuel injector; 
 a plurality of flow-through regions are configured in the nozzle body and positioned circumferentially and upstream of the valve seat, between which, in each case, there are guidance regions for the valve element; and 
 a plurality of spray-discharge orifices downstream from the valve seat; 
 wherein a number of the plurality of the spray-discharge orifices is different from a number of the flow-through regions; and 
 the geometry and the dimensions of the flow-through regions are equal, but the widths of the guidance surfaces of the guidance regions vary, so that there is a circumferentially asymmetrical distribution of the flow-through regions. 
 
     
     
       8. The fuel injector of  claim 1 , wherein at least two flow-through regions differ from each other in circumferential width such that a flow of the fuel is uniform.